The invention is directed to a method and apparatus for processing a collector ring used in an electrical device. More particularly, the invention relates to a method and apparatus for creating a groove or grooves in the surface of a collector ring used in an electrical device.
It is known to provide a spiral groove in the carbon brush contact surfaces of collector rings, particularly in collector rings of large industrial electrical generators or motors, and similar machinery. The grooves can serve various purposes. For example, the grooves help to reduce selective action of the brushes, which can cause catastrophic failure of the brush to ring contacts. After wear due to prolonged use, or after turning down, or re-truing of the collector ring contact surfaces, the grooves can be worn away, or become to shallow for optimal operation. For example, if the collector ring goes out of round, and needs to be re-trued, the re-truing operation can wear away the groove. Therefore, in such situations, the groove must be re-formed or enhanced in the contact surfaces of the collector rings. However, many of the known processes for initially creating such grooves, or for re-forming or enhancing such grooves are difficult to perform or are very time consuming. Therefore, it would be desirable to provide a new method and apparatus for creating or recreating grooves in the surfaces of collector rings.
One aspect of the invention relates to a method and apparatus for creating a groove in the surface of a collector ring for use in an electrical device. It is contemplated that the method and apparatus can be used to create a new groove in the surface of a collector ring having none. It is also contemplated that the method and apparatus can be used to enhance or re-form an existing groove in the surface of a collector ring.
One embodiment includes creating a groove in a surface of a collector ring by cutting the groove using a cutting tool that has a cutting action that functions independently from the motion of the collector ring.
Another embodiment includes positioning a covering or masking material over a portion of the surface of the collector ring to create a masked portion and an exposed portion of the surface of the collector ring. A groove is then created in the exposed portion of the surface of the collector ring. The masking material is then removed from the surface of the collector ring.